PNG Sequence with Pre-Multiplied Alpha

[Walter Soyka]

[Stephen Botting] “I don’t seem to be able to render PNG Sequences with pre-multiplied Alpha.”

Premultiplication violates the PNG spec [link]. PNG alpha is always supposed to be straight.

What is the problem you’re having? Can you show the issue and describe your workflow?

Walter Soyka
Designer & Mad Scientist at Keen Live [link]
Motion Graphics, Widescreen Events, Presentation Design, and Consulting
@keenlive   |   RenderBreak [blog]   |   Profile [LinkedIn]

[Stephen Botting]

[Walter Soyka] ”
Premultiplication violates the PNG spec [link]. PNG alpha is always supposed to be straight.

What is the problem you’re having? Can you show the issue and describe your workflow?
“

I wasn’t aware of that, thanks. I’ve done a little digging and it appears the Blackmagic ATEM doesn’t interpret PNG’s correctly. Looks like I’ll be switching to targa, for the ATEM. I thought I was having problems with CasparCG, but that has turned about to be ok.

Thanks for your help.

Cheers,
Stephen

https://www.43south.co.nz